This invention relates to an ink jet recording head that forms an image on a recording medium by ejecting ink droplets.
To achieve high quality printing with on-demand type ink jet recording apparatuses, it is necessary to increase their nozzle density. To this end, the specifications of U.S. Pat. Nos. 4,680,595 and 4,611,219, or Japanese Patent Laid-Open Publication No. 172/1981 propose ink jet recording heads that are constructed so that an array of nozzles formed on a common substrate is interposed by a group of pressure chambers so as to cause each pressure chamber to face each nozzle to thereby form a high density nozzle structure. These ink jet recording heads have a U-shaped ink preparation chamber which is arranged so as to not only surround one end of the group of pressure chambers but also to communicate with each of them.
However, in such a head structure, the U-shaped ink preparation chamber has a dead end. Once air bubbles are admitted into the ink preparation or supply chamber and remain in the dead end, it is difficult to purge them out. Also, with the U-shaped ink preparation chamber, the ink supply capacity differs between pressure chambers and this causes inconsistency in ink ejection characteristics such as the ink droplet diameter and ink ejection rate, thus presenting the problem of deteriorating the printing quality of the head.